|Publication number||US5554426 A|
|Application number||US 08/409,723|
|Publication date||10 Sep 1996|
|Filing date||24 Mar 1995|
|Priority date||24 Mar 1994|
|Also published as||CA2145254A1, DE4410148A1, EP0673762A2, EP0673762A3, EP0673762B1|
|Publication number||08409723, 409723, US 5554426 A, US 5554426A, US-A-5554426, US5554426 A, US5554426A|
|Inventors||Stefan Rober, Hans Jadamus, Hans Ries|
|Original Assignee||Huels Aktiengesellschaft|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (11), Referenced by (83), Classifications (47), Legal Events (10)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of the Invention
The invention relates to a multilayer plastic pipe.
2. Discussion of the Background
Plastic pipes of polyamide are known and are used for a variety of applications. To perform their function, the pipes have to be, inter alia, inert to the medium flowing in them and also resistant to high and low temperatures and mechanical stresses.
Single-layer pipes are not always able to fulfill the necessary requirements. For example, in the transport of aliphatic or aromatic solvents, fuels or the like, single layer pipes display considerable disadvantages, such as inadequate barrier action towards the medium, undesired dimensional changes or insufficient mechanical stressability. Reducing permeation is particularly important because the permissible emission values are being reduced ever further by legal requirements.
Attempts have been made to eliminate these disadvantages by means of multilayer pipes (DE-A 35 10 395; 37 15 251; 38 21 723; 40 01 125; 40 01 126). In practice these proposals can solve individual disadvantages, however, the overall property profile is still unsatisfactory.
FR-P 2 602 515 describes a two-layer pipe having an outer layer of polyamide 11 and an inner layer of plasticized polyvinylidene fluoride. Investigations have shown that the barrier action towards the medium flowing through is unsatisfactory. In particular, the permeation of methanol-containing fuels could not be reduced sufficiently.
The unpublished German Patent Application P 43 26 130.2 discloses thermoplastic multilayer composites of PVDF and polyamide. To achieve adhesion of the layers to one another, the PVDF contains small amounts of a polyglutarimide. However, multilayer pipes are not explicitly described.
Accordingly, one object of the present invention is a polyamide pipe having a good barrier action towards the medium being transported, in particular towards methanol-containing fuels.
Another object of the present invention is a polyamide pipe having satisfactory dimensional stability at high and low temperatures, and satisfactory mechanical stressability.
Still another object of the present invention is a polyamide multilayer pipe having layers that adhere to one another without the use of a layer of coupling agent, especially under prolonged action by the medium being transported.
These objects are achieved by a multilayer plastic pipe having at least
I. a layer based on a molding composition of polyamide (component I); and
II. a layer adjacent to layer I, based on a molding composition (component II) containing a mixture of
(a) from 97.5 to 50% by weight of polyvinylidene fluoride (component a); and
(b) from 2.5 to 50% by weight of an acrylate copolymer (component b),
with the layers adhering to one another.
The components a and b of layer II are preferably used in a weight ratio a:b of from 97.5:2.5 to 80:20 and particularly preferably from 96:4 to 90:10. Suitable components for layer I are, first and foremost, aliphatic homopolyamides and copolyamides. Examples which may be mentioned are 4.6, 6.6, 6.12, 8.10 and 10.10 polyamides or the like. Preference is given to 6, 10.12, 11, 12 and 12.12 polyamides (The numbering of the polyamides corresponds to the international standard, with the first digit(s) indicating the number of carbon atoms of the starting diamine and the last digit(s) indicating the number of carbon atoms of the dicarboxylic acid. If only one number is given, this means that the polyamide has been made from an α,ω-aminocarboxylic acid or from the lactam derived therefrom, see H. Domininghaus, Die Kunstoffe und ihre Eigenschaften, page 272, VDI (1976)). If copolyamides are used, these can contain, for example, adipic acid, sebacic acid, suberic acid, isophthalic acid or terephthalic acid as co-acid, or bis(4-aminocyclohexyl)methane, trimethylhexamethylenediamine, hexamethylenediamine or the like as co-diamine. The preparation of these polyamides are known (e.g.: D. B. Jacobs, J. Zimmermann, Polymerization Processes, p. 424-467; Interscience Publishers, New York (1977); DE-B 21 52 194).
Likewise suitable as polyamides are mixed aliphatic/aromatic polycondensates such as those described in, for example, U.S. Pat. Nos. 2,071,250, 2,071,251, 2,130,523, 2,130,948, 2,241,322, 2,312,966, 2,512,606, 3,393,210, or in Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd edition, vol. 18, Wiley & Sons (1982), pp. 328 and 435. Further polycondensates which are suitable as polyamides are poly(ether esteramides) or poly(etheramides). These products are described in, for example, DE-A 27 12 987, 25 23 991 and 30 06 961.
Both polyamides having predominantly amino terminal groups and those having predominantly carboxylic acid terminal groups can be used. Preference is given to polyamides having predominantly amino terminal groups.
The molecular weight (number average) of the polyamides is above 4,000, preferably above 10,000. The relative viscosity is here preferably in the range from 1.65 to 2.4 (DIN 53 727/ISO 307).
The polyamides can contain up to 40% by weight of other thermoplastics, if these do not interfere with the properties of the invention. In particular polycarbonate [H. Schnell, Chemistry and Physics of Polycarbonates, Interscience Publishers, New York (1981)], acrylonitrile-styrene-butadiene copolymers [Houben-Weyl, Methoden der organischen Chemie, vol. 14/1, Georg Thieme Verlag Stuttgart, pp. 393-406; Ullmanns Encyclopadie der technischen Chemie, 4th edition, vol. 19, Verlag Chemie Weinheim (1981), pp. 279-284], acrylonitrile-styrene-acrylate copolymers [Ullmanns Encyclopadie der technischen Chemie, 4th edition, vol. 19, Verlag Chemie Weinheim (1981), pp. 277-295], acrylonitrile-styrene copolymers [Ullmanns Encyclopadie der technischen Chemie, 4th edition, vol. 19, Verlag Chemie Weinheim (1981), p. 273 ff.] or polyphenylene ethers (DE-A 32 24 691 and 32 24 692; U.S. Pat. Nos. 3,306,874, 3,306,875 and 4,028,341), should be mentioned here.
If required, the polyamides can be toughened. Suitable modifiers are, for example, ethylene-propylene or ethylene-propylene-diene copolymers (EP-A-0 295 076), polypentenylene, polyoctenylene or random or block copolymers of alkenylaromatic compounds and aliphatic olefins or dienes (EP-A-0 261 748). Furthermore, the impact-toughening rubbers can be core/shell rubbers having a viscoelastic core of (meth)acrylate, butadiene or styrenebutadiene rubber with glass transition temperatures Tg <-10° C. The core may be crosslinked.
The shell can be built up of styrene and/or methyl methacrylate and/or further unsaturated monomers (DE-A 21 44 528, 37 28 685). The proportion of impact-toughening components should be selected so that the desired properties are not impaired.
Component a of layer II contains polyvinylidene fluoride, which is preferably used in unplasticized form. Preparation and structure of the polymer is known (Hans R. Kricheldorf, Handbook of Polymer Synthesis, Part A, Verlag Marcel Dekker Inc. New York--Basel--Hongkong, pp. 191 ff.; Kunststoff-Handbuch, 1st edition, vol. XI, Carl Hanser Verlag Munich (1971), pp. 403 ff.).
The polyvinylidene fluoride present can also be a copolymer based on vinylidene fluoride, which contains up to 40% by weight of other monomers. Examples of other monomers are trifluoroethylene, ethylene, propene and hexafluoropropene.
The polyvinylidene fluoride used according to the invention generally has a melt flow index of <17 g/10 min, preferably from 2 to 13 g/10 min (DIN 53 735).
The component b of layer II is an acrylate copolymer containing at least the following basic building blocks:
(i) from 14 to 85% by weight, preferably from 35 to 70% by weight, of ##STR1## (ii) from 0 to 75% by weight, preferably from 10 to 75% by weight, more preferably 20 to 40% by weight, of ##STR2## (iii) from 0 to 15% by weight of ##STR3## (iiii) from 7 to 20% by weight, preferably from 8 to 12% by weight, of ##STR4## In the specified formulae, Alkyl is methyl, ethyl, propyl, butyl, pentyl or hexyl,
R1 to R5 is H or (Cn H2n+1), with n=1 to 6 and m=0 or 1, with the radicals R1 to R5 being either identical or different. Preferably R1 to R5 are all methyl radical, Alkyl is methyl and m is 1.
The acrylate copolymers are prepared in a known manner by polymerization of the corresponding monomers. In the case of m=0 and R4 =H, the basic building block (iiii) is derived, for example, from maleic anhydride, while in the case of m=1, the basic building block (iiii) is formed by saponification of two adjacent units of the component (i) and subsequent cyclization. The acrylate copolymers used according to the invention generally have a melt flow index of <30 g/10 min, preferably from 0.2 to 15 g/10 min.
In a preferred embodiment, the basic building block (ii) is present in an amount of from 10 to 75% by weight, particularly preferably from 20 to 40% by weight. Such polymers are also described as polyglutarimides. These are poly(alkyl acrylates), in which two adjacent carboxylate groups have been reacted to form a cyclic acid imide. The imide formation is preferably carried out using ammonia or primary amines, such as, methylamine. Here, because of the presence of water in the imide formation reaction, part of the basic building blocks (i) is saponified to give the basic building blocks (iii) and (iiii). The products and their preparation are known (Hans R. Kricheldorf, Handbook of Polymer Synthesis, Part A, Verlag Marcel Dekker Inc. New York--Basel--Hongkong, pp. 223 ff.; H. G. Elias, Makromolekule, Huthig und Wepf Verlag Basel--Heidelberg--New York; U.S. Pat. Nos. 2,146,209, 4,246,374).
To increase the low-temperature impact toughness, the acrylate copolymers can additionally contain appropriate modifiers. Examples are core/shell polymers having a polybutyl acrylate core and a shell of polymethyl methacrylate and/or polyglutarimide. Apart from the examples given, further modifiers are possible.
Conventional auxiliaries and additives which may be added to the molding compositions for the layers I and II are for example, flame retardants, stabilizers, plasticizers, processing aids, viscosity improvers, fillers, additives for improving the electrical conductivity, pigments or the like. The amount added of the specified agents is to be selected so that the desired properties are not seriously affected.
The preparation of the molding composition for layer II is carried out according to conventional and known processes of melt mixing of the components a and b of layer II in a mixer providing good compounding, in for example, a twin-screw compounder, at temperatures which depend on the melting points of the components a and b, generally at temperatures between 200° and 300° C.
The preparation of the composition for layer II from the components a and b can also be carried out directly in the processing extruder in which the composition is processed for the production of the thermoplastic multilayer composite with the layer I.
The smaller the content of component b in the molding composition for layer II, the larger the barrier action towards the medium being transported. For example, the barrier action towards methanol-containing fuels of mixtures comprising 95% by weight of polyvinylidene fluoride polymers (component a) and 5% by weight of an acrylate copolymer of the invention (component b) is only inconsequentially smaller than the barrier action of pure polyvinylidene fluoride.
The multilayer pipes can further contain more layers of polyvinylidene fluoride polymers which are adjacent to layer II, but not to layer I. Likewise, the multilayer pipes can contain more layers of polyamide which are adjacent to layer I or layer II. In particular, the pipes can contain additional layers with the composition of layer I and/or II which have been made electrically conductive and have a surface resistance of less than 109 Ω. These layers which have been made electrically conductive are preferably on the inside. A further embodiment has layer II itself electrically conductive.
The layers are made electrically conductive by known methods. For example, an addition is made of up to about 15% by weight of, conductivity black, carbon fibers, metal powders, or the like.
The multilayer pipes of the invention can also contain, in addition to the layers I and II,
(c) at least one layer based on a polyolefin; and
(d) at least one layer based on a conventional coupling agent for bonds between polyolefin and polyamide,
with the layer of coupling agent directly between layer I (or a layer with this composition) and the layer based on a polyolefin.
Examples of polyolefins are polyethylene and polypropylene. In principle, any commercial type can be used. Examples are linear polyethylene of high, medium or low density; LDPE; ethylene copolymers containing relatively small amounts (up to a maximum of about 40% by weight) of comonomers such as n-butyl acrylate, methyl methacrylate, maleic anhydride, styrene, vinyl alcohol or the like; isotactic or atactic homopolypropylene; random copolymers of propene with ethene and/or 1-butene; ethylene-propylene block copolymers; and other similar polymers. Such polyolefins can also contain an impact-toughening component such as EPM or EPDM rubber, or SEBS.
Suitable coupling agents for bonds between polyolefins and polyamide are known. They are based on polyolefin which is modified by suitable reactive groups. The reactive groups can be introduced either by copolymerization together with the olefin, or by means of a grafting reaction. In the grafting reaction, a preformed polyolefin is reacted in a known manner with an unsaturated functional monomer and, advantageously, a free-radical donor at elevated temperature.
Suitable reactive groups are, for example, acid anhydride groups, carboxylic acid groups, epoxide groups, oxazoline groups or trialkoxysilane groups. Of these, preference is given to acid anhydride groups. Coupling agents containing more than 0.1% by weight of anhydride groups are particularly suitable.
Suitable coupling agents are available, inter alia, under the trade names BYNEL (DuPont), PRIMACOR (Dow), POLYBOND (BP), OREVAC (Elf), HERCOPRIME (Hercules), EPOLENE (Eastman), HOSTAMONT (Hoechst), EXXELOR (Exxon) and ADMER (Mitsui Petrochemical). The coupling agents are selected according to the criteria which are known to those skilled in the art with the aid of the corresponding product descriptions. In the multilayer pipes of the present invention, all adjacent layers adhere to one another.
Table 1 shows some examples of layer arrangements in multilayer plastic pipes of the present invention.
In a preferred embodiment, the layers are arranged and the thicknesses of the layers are selected so that layers with a composition of layer II lie as close as possible to the middle of the multilayer pipe wall. This measure improves the low-temperature impact toughness of the multilayer pipes.
Furthermore, it is preferred that the thicknesses of layers with a composition of layer II are selected so that it makes up from 2 to 40% of the total wall thickness and, in particular, from 5 to 30% of the total wall thickness of the multilayered pipe. The manufacture of the multilayer plastic pipes can be carried out, for example, by coextrusion.
The multilayer plastic pipes of the present invention have exceptionally good resistance and barrier action against diffusion towards chemical agents, solvents and fuels. In addition, the layers adhere to one another so that, for example, on thermal expansion, bending or thermoforming of the multilayer pipe, no separation of the various layers from one another occurs. This good adhesion between the layers is maintained even on prolonged contact with fuels, even methanol-containing fuels.
TABLE 1______________________________________Layer arrangement of multilayer plastic pipes ofthe invention (buildup from outside to inside)Layer arrangement No. Configuration______________________________________1 Layer I Layer II2 Layer I Layer II (conductive)3 Layer I Layer II Layer I4 Layer I Layer II Layer I (conductive)5 Layer I Layer II Layer I Layer II Layer I6 Layer I Layer II Layer I Layer II (conductive)7 Layer I Layer II Layer I Layer II Layer I (conductive8 Layer I Layer II Layer of polyvinylidene fluoride copolymers9 Layer I Layer II Layer of polyvinylidene fluoride copolymers (conductive)10 Layer I Layer I (other type of polyamide) Layer II11 Layer II Layer I12 Layer of polyolefin Layer of coupling agent Layer I Layer II______________________________________
The plastic pipes of the invention are preferably used for the transport of petrochemicals or for brake fluid, cooling hydraulic fluids or fuel, including methanol or ethanol containing fuel. They may be shaped as a straight, corrugated or convoluted tubing. A further application of the multilayer pipes is the manufacture of hollow bodies such as tanks or filling ports, in particular for the motor vehicles. The manufacture of these hollow bodies can be carried out, for example, by coextrusion followed by blow molding.
Other features of the invention will become apparent in the course of the following descriptions of exemplary embodiments which are given for illustration of the invention and are not intended to be limiting thereof.
The parameters specified were determined by means of the following measurement methods.
The determination of the solution viscosity (relative viscosity ηrel) of the polyamides was carried out using a 0.5% by weight m-cresol solution at 25° C., in accordance with DIN 53 727/ISO 307.
For determination of the amino terminal groups, 1 g of the polyamides was dissolved in 50 ml of m-cresol at 25° C. The solution was titrated potentiometrically with perchloric acid.
For determination of the carboxyl terminal groups in the polyamides, 1 g of polycondensate was dissolved in 50 ml of benzyl alcohol under a blanket of nitrogen at 165° C. The solution time was a maximum of 20 minutes. The solution was titrated with a solution of KOH in ethylene glycol (0.05 mol KOH/l) against phenolphthalein until the color changed.
The determination of the melt flow index of the acrylate copolymers was carried out at 230° C. and under a load of 3.8 kg (DIN 53 735).
The determination of the melt flow index of the polyvinylidene fluorides was carried out at 230° C. and under a load of 5 kg (DIN 53 735).
The testing of the mechanical separability at the interface was carried out using a metal wedge (cutting angle: 5 degrees; loading weight: 2.5 kg) which was used to try to separate the material interface layer to be tested. If separation occured at the interface between the components, the adhesion was poor. If, on the other hand, separation occurs completely or partially within one of the two components, good adhesion was present.
The determination of the diffusion of fuel constituents was carried out on pipes using a fuel mixture (fuel M 15: 42.5 parts by volume of isooctane, 42.5 parts by volume of toluene and 15 parts by volume of methanol) at 60° C. The test specimens, having a length of 500 mm, had the fuel mixture running through the inside. The determination of the fuel diffusion was carried out by the activated carbon adsorption method. The diffusion was measured as loss in mass over time (measurement every 24 hours). The measure given was the loss in mass recorded per unit area which was measured when the diffusion process was at equilibrium, i.e. when the loss in mass determined per 24 hours no longer changed with time.
Examples denoted by letters are Comparative Examples.
PA 1: Polyamide 12 (ηrel : 2.1; plasticizer content: 0; amino terminal group content: 9 mmol/kg; carboxyl terminal group content: 48 mmol/kg; VESTAMID® L 2140--HULS AG)
PA 2: Polyamide 12 (ηrel : 2.1; plasticizer content per 100 parts by weight of polyamide: 15 parts by weight of N-n-butylbenzenesulphonamide; amino terminal group content: 9 mmol/kg; carboxyl terminal group content: 48 mmol/kg; VESTAMID® L 2124--HULS AG)
PA 3: Polyamide 12 (ηrel : 2.1; plasticizer content per 100 parts by weight of polyamide: 15 parts by weight of N-n-butylbenzenesulphonamide; amino terminal group content: 50 mmol/kg; carboxyl terminal group content: 8 mmol/kg)
PA 4: Polyamide 612(ηrel : 1.9; plasticizer content: 0; amino terminal group content: 93 mmol/kg; carboxyl terminal group content: 29 mmol/kg)
PA 5: Molding composition consisting of
a. 100 parts by weight of polyamide 12 (ηrel : 2.1; plasticizer content: 0; amino terminal group content: 9 mmol/kg; carboxyl terminal group content: 48 mmol/kg)
b. 4 parts by weight of commercial conductivity black (Ketjenblack® EC 300--AKZO)
PVDF 1: Polyvinylidene fluoride (melt flow index: 13 g/10 min, DYFLOR® LE--HULS AG).
PVDF 2: Polyvinylidene fluoride (melt flow index: 8.5 g/10 min, DYFLOR® EE--HULS AG)
PVDF 3: Polyvinylidene fluoride consisting of
(1) 100 parts by weight of polyvinylidene fluoride (melt flow index: 8.5 g/10 min, DYFLOR® EE--HULS AG)
(2) 6 parts by weight of commercial conductivity black (Ketjenblack® EC 300--AKZO).
The polymers used for the component b of layer II are built up of the building blocks denoted above by (i) to (iiii), with Alkyl and R1 to R5 being methyl in each case and m being 1.
TABLE 2______________________________________ P1 P2 P3 P4______________________________________% by weight of i) 100 14 11 57% by weight of ii) 0 86 80 30% by weight of iii) 0 0 6 3% by weight of iiii) 0 0 3 10Melt flow index 0.8 0.4 0.4 0.4[g/10 min]______________________________________Z1: Mixture consisting of (a) 50% by weight of PVDF 1; and (b) 50% by weight of P1Z2: Mixture consisting of (a) 50% by weight of PVDF 1; and (b) 50% by weight of P2Z3: Mixture consisting of (a) 50% by weight of PVDF 1; and (b) 50% by weight of P3Z4: Mixture consisting of (a) 50% by weight of PVDF 1; and (b) 50% by weight of P4Z5: Mixture consisting of (a) 90% by weight of PVDF 1; and (b) 10% by weight of P4Z6: Mixture consisting of (a) 95% by weight of PVDF 2; and (b) 5% by weight of P4Z7: Mixture consisting of (a) 90% by weight of PVDF 3; and (b) 10% by weight of P4______________________________________
The preparation of the mixtures was carried out in a twin-screw compounder at a composition temperature of 260° C.
The pipes were produced on a laboratory extrusion facility using a five-layer die (in the production of the two-, three- and four-layer pipes, the channels not required remain closed) (See Tables 3 and 4). The barrel temperatures were 230° C. (PA 1, PA 2, PA 3); 250° C. (PVDF 1, PVDF 2, PVDF 3, Z 1 to Z 7) and 280° C. (PA 4, PA 5). The tubes produced had an external diameter of 8 mm and a total wall thickness of 1 mm.
TABLE 3__________________________________________________________________________Comparative Examples Mechanically separable at theComposition of interfaces layers from Diffusion [g/(d after storage after storageExperiment outside to inside m.sup.2)] at 60° C. at 23° in fuel(*)__________________________________________________________________________A PA 1 (1.0 mm) 600 (***) (***)(single-layer pipe)B PA 2 (1.0 mm) 410 (***) (***)(single-layer pipe)C PA 1 (0.9 mm) 30 yes yes PVDF 1 (0.1 mm)D PA 3 (0.9 mm) (**) yes yes Z 1 (0.1 mm)E PA 2 (0.8 mm) 30 yes yes Z 1 (0.1 mm) (PA 2 from Z 1) (PA 2 from Z 1) PVDF 1 (0.1 mm)F PA 3 (0.9 mm) (**) yes yes Z 2 (0.1 mm)G PA 4 (0.9 mm) (**) yes yes Z 3 (0.1 mm)__________________________________________________________________________ (*) Storage at 23° C. for 20 days in standard fuel M 15 (42.5% by volume of isooctane, 42.5% by volume of toluene and 15% by volume of methanol) (**) Diffusion was not determined. (***) Singlelayer pipe; there is no interface.
TABLE 4__________________________________________________________________________Experiments according to the invention Mechanically separable at theComposition of interfaces layers from Diffusion [g/(d after storage after storageExperiment outside to inside m.sup.2)] at 60° C. at 23° in fuel(*)__________________________________________________________________________1 PA 1 (0.8 mm) 40 no no Z 5 (0.2 mm)2 PA 1 (0.9 mm) 60 no no Z 6 (0.1 mm)3 PA 2 (0.8 mm) <30 no no Z 6 (0.1 mm) PVDF 1 (0.1 mm)4 PA 2 (0.8 mm) 50 no no Z 6 (0.1 mm) PVDF 3 (0.05 mm)5 PA 3 (0.9 mm) 75 no no Z 7 (0.1 mm)6 PA 4 (0.8 mm) <35 no no Z 4 (0.1 mm) PVDF 2 (0.1 mm)7 PA 2 (0.45 mm) 60 no no Z 6 (0.1 mm) PA 2 (0.45 mm)8 PA 2 (0.45 mm) <60 no no Z 6 (0.1 mm) PA 3 (0.4 mm) Z 7 (0.05 mm)9 PA 1 (0.8 mm) 70 no no Z 5 (0.1 mm) PA 5 (0.1 mm)10 PA 2 (0.3 mm) <60 no no Z 6 (0.05 mm) PA 2 (0.3 mm) Z 6 (0.05 mm) PA 2 (0.3 mm)11 PA 1 (0.5 mm) 65 no no Z 5 (0.05 mm) PA 1 (0.3 mm) Z 5 (0.05 mm) PA 5 (0.1 mm)12 Z 6 (0.2 mm) 60 no no PA 3 (0.8 mm)__________________________________________________________________________ (*) Storage at 23° C. for 20 days in standard fuel M 15 (42.5% by volume of isooctane, 42.5% by volume of toluene and 15% by volume of methanol).
As can be seen from Table 4, Experiments 1-12, which correspond to the present invention, exhibit low diffusion of fuels (75 g/dm2 or less, at 60° C.), and good adhesion (no separability at the interfaces). In contrast, Table 3, with the results of Experiments A-G, Comparative Examples, exhibit high diffusion of fuels (600 or 412 g/dm2 at 60° C.), or poor adhesion (separability at the interfaces). The Experiments which correspond to the present invention are superior to the Comparative Examples.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US5258213 *||9 Jan 1992||2 Nov 1993||Huels Aktiengesellschaft||Multilayer thermoplastic composites|
|US5313987 *||16 Apr 1993||24 May 1994||Huels Aktiengesellschaft||Multilayer plastic pipe comprising an outer polyamide layer and a layer of a molding formed from a mixture of thermoplastic polyester and a compound having at least two isocyanate groups|
|US5362529 *||12 Feb 1993||8 Nov 1994||Huels Aktiengesellschaft||Thermoplastic laminates|
|US5362570 *||16 Nov 1992||8 Nov 1994||Huels Aktiengesellschaft||Thermoplastic multilayer composites|
|US5389410 *||10 Nov 1992||14 Feb 1995||Huels Aktiengesellschaft - Pb 15||Thermoplastic multilayer composites of polyamide and linear crystalline polyester blends|
|US5404915 *||10 Nov 1992||11 Apr 1995||Huels Aktiengesellschaft||Multilayer plastic pipe|
|US5425817 *||10 Nov 1992||20 Jun 1995||Huels Aktiengesellschaft||Multilayer plastic pipe with polyamide inner and outer layers and a linear crystalline polyester intermediate layer|
|US5449024 *||3 Dec 1993||12 Sep 1995||Huels Aktiengesellschaft||Multilayer plastic pipe|
|US5472784 *||28 Jan 1994||5 Dec 1995||Huels Aktiengesellschaft||Thermoplastic multilayer composites|
|US5474822 *||28 Jan 1994||12 Dec 1995||Huels Aktiengesellschaft||Multilayer plastic pipe|
|US5478620 *||28 Feb 1994||26 Dec 1995||Huels Aktiengesellschaft||Multilayer plastic pipe|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US5779954 *||13 Mar 1996||14 Jul 1998||Solvay (Societe Anonyme)||Process for manufacturing a hollow body|
|US5858492 *||29 Feb 1996||12 Jan 1999||Huels Aktiengesellschaft||Thermoplastic multilayer composites|
|US6040025 *||11 May 1998||21 Mar 2000||Elf Atochem S.A.||Adhesion binder containing glutarimide moieties|
|US6068026 *||22 Jan 1998||30 May 2000||Hutchinson||Thermoplastic-elastomer composite product, such as a pipe for conveying coolant in an air conditioning circuit, for example|
|US6090459 *||7 Jul 1997||18 Jul 2000||Huels Aktiengesellschaft||Multilayer plastic composition having an electrically conductive inner layer|
|US6143415 *||24 Oct 1994||7 Nov 2000||Elf Atochem S.A.||Adhesive bonding agent for PVDF, its application as barrier material and material obtained from the latter|
|US6428866 *||12 Nov 1999||6 Aug 2002||Degussa-Huels Aktiengesellschaft||Multilayer plastic composition having an electrically conductive inner layer|
|US6455118 *||10 Dec 1998||24 Sep 2002||Institut Francais Du Petrole||Flexible pipeline having a dual-layer sheath of polymer|
|US6467508||12 Oct 2001||22 Oct 2002||Atofina Chemicals, Inc.||Low precipitate polyamide based tubing|
|US6616191 *||2 Nov 1995||9 Sep 2003||Atofina||Pipes, based on polyamide and polyolefin, for gas transmission and/or distribution|
|US6680093 *||15 May 1998||20 Jan 2004||Degussa Ag||Multilayer composites|
|US6742952||28 Feb 2003||1 Jun 2004||Bic Corporation||Transparent or translucent tubular structure|
|US6766091||26 Jun 2003||20 Jul 2004||Degussa Ag||Polymeric optical conductors|
|US6780935 *||30 Jan 2001||24 Aug 2004||Atofina Chemicals, Inc.||Fluoropolymer resins containing ionic or ionizable groups and products containing the same|
|US6872781 *||24 Sep 2003||29 Mar 2005||Arkema Inc.||Fluoropolymer resins containing ionic or ionizable groups and products containing the same|
|US6893729||19 Feb 2001||17 May 2005||Daikin Industries, Ltd.||Layered resin molding and multilayered molded article|
|US6964800||28 May 2002||15 Nov 2005||Nyltec Italia||Plastic-based multilayer structure and tube having a multilayer structure|
|US7175896||9 Oct 2003||13 Feb 2007||Degussa Ag||Composite having two or more layers, including an EVOH layer|
|US7449111||14 Jul 2004||11 Nov 2008||Arkema Inc.||Resins containing ionic or ionizable groups with small domain sizes and improved conductivity|
|US7579058||13 Mar 2007||25 Aug 2009||Degussa Gmbh||Air brake line|
|US7601771||13 Jun 2003||13 Oct 2009||Goldschmidt Gmbh||Polymer compositions containing polymers and ionic liquids|
|US7939151||21 Jul 2005||10 May 2011||Evonik Degussa Gmbh||Coolant line|
|US8039160||14 Jul 2004||18 Oct 2011||Arkema Inc.||Multi-layer polyelectrolyte membrane|
|US8048504||22 Feb 2006||1 Nov 2011||Evonik Degussa Gmbh||Composite having two or more layers, including an EVOH layer|
|US8133561||10 Aug 2005||13 Mar 2012||Evonik Degussa Gmbh||Multi-layer composite comprising an EVOH layer and a protective layer|
|US8221890||3 Oct 2005||17 Jul 2012||Evonik Degussa Gmbh||Multilayer composite having a polyester layer and a protective layer|
|US8357455||9 Nov 2005||22 Jan 2013||Evonik Degussa Gmbh||Transparent moulding compound|
|US8470433||4 Jan 2006||25 Jun 2013||Evonik Degussa Gmbh||Transparent decoratable multilayer film|
|US8614005||21 Dec 2011||24 Dec 2013||Evonik Degussa Gmbh||Polyamide blend film|
|US8975330 *||14 Oct 2010||10 Mar 2015||Solvay Specialty Polymers Italy S.P.A.||Coating composition|
|US9505912||7 Aug 2007||29 Nov 2016||Basf Se||Polyamide molding materials with improved thermal aging and hydrolysis stability|
|US20030012909 *||6 Mar 2001||16 Jan 2003||Stephane Jung||Double-layer pipe|
|US20030072987 *||11 Oct 2002||17 Apr 2003||Degussa Ag||Conduit system for fluids and gases in a fuel cell|
|US20030124281 *||27 Dec 2002||3 Jul 2003||Degussa Ag||Liquid-or vapor-conducting system with a jointing zone made from a coextruded multilayer composite|
|US20030148125 *||19 Feb 2001||7 Aug 2003||Takeshi Inaba||Layered resin molding and multilayered molded article|
|US20040001682 *||26 Jun 2003||1 Jan 2004||Degussa Ag||Polymeric optical conductors|
|US20040092661 *||24 Sep 2003||13 May 2004||Lotfi Hedhli||Fluoropolymer resins containing ionic or ionizable groups and products containing the same|
|US20040140668 *||26 Sep 2003||22 Jul 2004||Degussa Ag||Pipe connection|
|US20040175625 *||6 Mar 2003||9 Sep 2004||Lotfi Hedhli||Non-perfluorinated resins containing ionic or ionizable groups and products containing the same|
|US20040265527 *||9 Oct 2003||30 Dec 2004||Degusa Ag||Composite having two or more layers, including an EVOH layer|
|US20050077233 *||14 Jul 2004||14 Apr 2005||Lotfi Hedhli||Resins containing ionic or ionizable groups with small domain sizes and improved conductivity|
|US20050268501 *||3 Jun 2004||8 Dec 2005||Janet Feinstein||Activity scheduling device|
|US20060014067 *||14 Jul 2004||19 Jan 2006||Lotfi Hedhli||Multi-layer polyelectrolyte membrane|
|US20060057391 *||14 Sep 2005||16 Mar 2006||Anthony Bonnet||Structure comprising at least one polyethylene layer and at least one layer of barrier polymer|
|US20060078752 *||11 Oct 2005||13 Apr 2006||Degussa Ag||Line system for fluids and gases in a fuel cell|
|US20060083882 *||3 Oct 2005||20 Apr 2006||Degussa Ag||Multilayer composite having a polyester layer and a protective layer|
|US20060099478 *||11 Oct 2005||11 May 2006||Degussa Ag||Line system for fluids and gases in a fuel cell|
|US20060100323 *||13 Jun 2003||11 May 2006||Creavis Gesellschaft Fuer Technologie Und Inno.||Polymer compositions containing polymers and ionic liquids|
|US20060141188 *||22 Feb 2006||29 Jun 2006||Degusa Ag||Composite having two or more layers, including an EVOH layer|
|US20070104971 *||26 Oct 2006||10 May 2007||Degussa Ag||Film with outer layer composed of a polyamide composition|
|US20070134458 *||4 Feb 2005||14 Jun 2007||Lovett Brad A||Aromatic polyamide tubing for vehicle applications|
|US20070148388 *||21 Jul 2005||28 Jun 2007||Karl Kuhmann||Coolant line|
|US20070166560 *||9 Jun 2005||19 Jul 2007||Degussa Ag||Multilayer foil|
|US20070231520 *||13 Mar 2007||4 Oct 2007||Degussa Ag||Air brake line|
|US20070259147 *||23 Aug 2004||8 Nov 2007||John Alexandre Boudry||Pipe|
|US20070259240 *||26 Jun 2007||8 Nov 2007||Lotfi Hedhli||Non-Perfluorinated Resins Containing Ionic or Ionizable Groups and Products Containing the Same|
|US20080119632 *||9 Nov 2005||22 May 2008||Degussa Gmbh||Transparent Moulding Compound|
|US20080166529 *||4 Jan 2006||10 Jul 2008||Degussa Gmbh||Transparent Moulding Compound|
|US20080185065 *||9 Jun 2006||7 Aug 2008||Uponor Innovation Ab||Multilayer Pipe|
|US20080213552 *||4 Jan 2006||4 Sep 2008||Degussa Gmbh||Transparent Decoratable Multilayer Film|
|US20080261010 *||4 Jan 2006||23 Oct 2008||Degussa Gmbh||Polyamide Blend Film|
|US20080317986 *||10 Aug 2005||25 Dec 2008||Guido Schmitz||Multi-Layer Composite Comprising an Evoh Layer and a Protective Layer|
|US20090130357 *||14 Jul 2006||21 May 2009||Veritas Ag||Hollow body with double barrier layer|
|US20100221551 *||14 May 2010||2 Sep 2010||Evonik Degussa Gmbh||Multilayer foil|
|US20120202935 *||14 Oct 2010||9 Aug 2012||Solvay Specialty Polymers Italy S.P.A.||Coating composition|
|US20160060459 *||25 Aug 2015||3 Mar 2016||Evonik Degussa Gmbh||Metallic pipe having a hydrolysis-resistant layer of a polyamide moulding composition|
|CN101506286B||7 Aug 2007||21 Sep 2011||巴斯夫欧洲公司||Polyamide molding materials with improved thermal aging and hydrolysis stability|
|CN102712824A *||14 Oct 2010||3 Oct 2012||索尔维特殊聚合物意大利有限公司||Coating composition|
|CN102712824B *||14 Oct 2010||11 May 2016||索尔维特殊聚合物意大利有限公司||涂覆组合物|
|EP1177221A1 *||15 Feb 2001||6 Feb 2002||Atofina Chemicals, Inc.||Fluoropolymer resins containing ionic or ionizable groups and products containing the same|
|EP1177221A4 *||15 Feb 2001||8 Nov 2006||Arkema Inc||Fluoropolymer resins containing ionic or ionizable groups and products containing the same|
|EP1270209A1 *||19 Feb 2001||2 Jan 2003||Daikin Industries, Ltd.||Layered resin molding and multilayered molded article|
|EP1270209A4 *||19 Feb 2001||16 Jun 2004||Daikin Ind Ltd||Layered resin molding and multilayered molded article|
|EP1302308A1 *||17 Sep 2002||16 Apr 2003||Atofina Chemicals, Inc.||Low precipitate polyamide based tubing|
|EP3069875A1||17 Mar 2015||21 Sep 2016||Evonik Degussa GmbH||Multilayer compound with one fluoropolymer layer|
|WO2001038076A1 *||22 Nov 2000||31 May 2001||Lithium Power Technologies, Inc.||Low cost polyvinylidene fluoride copolymers and methods of manufacture thereof|
|WO2002062567A2 *||5 Feb 2002||15 Aug 2002||Atofina||Multilayer structure having a fluorinated polymer layer|
|WO2002062567A3 *||5 Feb 2002||23 Jun 2005||Atofina||Multilayer structure having a fluorinated polymer layer|
|WO2005018927A1 *||23 Aug 2004||3 Mar 2005||Petrotechnik Limited||Pipe with inner and outer layers formed from fluoropolymers|
|WO2011045375A2||14 Oct 2010||21 Apr 2011||Solvay Solexis S.P.A.||Coating composition|
|WO2011045375A3 *||14 Oct 2010||30 Jun 2011||Solvay Solexis S.P.A.||Coating composition|
|WO2017121961A1 *||12 Jan 2017||20 Jul 2017||Arkema France||Multilayer tubular structure having improved resistance to extraction in biogasoline and use thereof|
|WO2017121962A1 *||12 Jan 2017||20 Jul 2017||Arkema France||Multilayer tubular structure having improved resistance to extraction in biogasoline and use thereof|
|U.S. Classification||428/36.91, 428/476.3, 428/475.8, 428/922, 428/474.9, 138/118, 138/DIG.7, 428/36.6, 428/475.2, 428/474.4, 428/421, 138/137, 138/140, 206/524.5, 138/141, 428/480|
|International Classification||B32B27/34, B60K15/03, B32B27/30, F16L9/12, B32B1/08, B32B27/08, B32B1/02|
|Cooperative Classification||B32B2307/202, B32B27/34, B32B27/08, B32B2307/718, B32B7/12, B32B2309/105, B32B27/304, B32B27/308, B32B27/32, B32B1/08, Y10T428/31786, Y10T428/31736, Y10T428/3175, Y10T428/31743, Y10T428/3154, Y10T428/31732, Y10T428/31725, F16L9/12, Y10T428/1379, Y10T428/1393, Y10S138/07, Y10S428/922|
|European Classification||F16L9/12, B32B27/08|
|24 Mar 1995||AS||Assignment|
Owner name: HUELS AKTIENGESELLSCHAFT, GERMANY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ROEBER, STEFAN;JADAMUS, HANS;RIES, HANS;REEL/FRAME:007424/0184;SIGNING DATES FROM 19941108 TO 19941125
|17 Feb 2000||FPAY||Fee payment|
Year of fee payment: 4
|31 May 2001||AS||Assignment|
Owner name: DEGUSSA-HUELS AKTIENGESELLSCHAFT, GERMANY
Free format text: MERGER;ASSIGNOR:HUELS AKTIENGESELLSCHAFT;REEL/FRAME:011837/0001
Effective date: 19990201
|11 Jan 2002||AS||Assignment|
Owner name: DEGUSSA AG, GERMANY
Free format text: CHANGE OF NAME;ASSIGNOR:DEGUSSA-HUELS AKTIENGESELLSCHAFT;REEL/FRAME:012463/0601
Effective date: 20010209
|31 Mar 2004||REMI||Maintenance fee reminder mailed|
|14 May 2004||SULP||Surcharge for late payment|
Year of fee payment: 7
|14 May 2004||FPAY||Fee payment|
Year of fee payment: 8
|7 Mar 2008||FPAY||Fee payment|
Year of fee payment: 12
|22 Feb 2010||AS||Assignment|
Owner name: EVONIK DEGUSSA GMBH,GERMANY
Free format text: CHANGE ADDRESS;ASSIGNOR:EVONIK DEGUSSA GMBH;REEL/FRAME:023985/0296
Effective date: 20071031
Owner name: DEGUSSA GMBH,GERMANY
Free format text: CHANGE OF ENTITY;ASSIGNOR:DEGUSSA AG;REEL/FRAME:023998/0937
Effective date: 20070102
Owner name: EVONIK DEGUSSA GMBH, GERMANY
Free format text: CHANGE ADDRESS;ASSIGNOR:EVONIK DEGUSSA GMBH;REEL/FRAME:023985/0296
Effective date: 20071031
Owner name: DEGUSSA GMBH, GERMANY
Free format text: CHANGE OF ENTITY;ASSIGNOR:DEGUSSA AG;REEL/FRAME:023998/0937
Effective date: 20070102
|23 Feb 2010||AS||Assignment|
Owner name: EVONIK DEGUSSA GMBH,GERMANY
Free format text: CHANGE OF NAME;ASSIGNOR:DEGUSSA GMBH;REEL/FRAME:024006/0127
Effective date: 20070912
Owner name: EVONIK DEGUSSA GMBH, GERMANY
Free format text: CHANGE OF NAME;ASSIGNOR:DEGUSSA GMBH;REEL/FRAME:024006/0127
Effective date: 20070912